As our houses are warmed, so also our bodies are maintained at a certain temperature, about 98.4° to 98.6°. In our homes, the fires are kept burning in our furnaces; so in our bodies, heat is generated by a process similar to fire, the fire being essentially the same as any other fire, the union of the oxygen of the air with the carbon of the fuel. No matter how rapidly or how slowly these elements unite, whether in the furnace, or in the body, or in the decaying log, heat is given off.
In the body, food is the fuel that furnishes the carbon, and the breath is the air that furnishes the oxygen. The union of carbon and oxygen does not take place in the stomach or in the lungs, but in the various tissues to which they are carried by the blood. The body is thus, as it were, all on fire.
To satisfy the demand for heat, we have a certain class of foods especially rich in carbon, and therefore well suited to the maintaining of normal temperature. This class is known as the “carbonaceous group,” and includes starches, fats, and sugars.
While our bodies must be supplied with heat, it is quite as important that they possess an ample store of energy for work and exercise, in order that we may perform life’s duties. In physics, we are taught that heat is one form or manifestation of force, and that heat may at will be converted into force, and force into heat. This is true of the heat and energy furnished by our carbonaceous foods. The fats are the great heat producers, while the starches,/ furnish most of the energy.
Starch comes from vegetable foods, chiefly the cereal grains, but also the potato and the banana.
Fats are found in olives ; in nuts ; in milk and cream ; in butter ; in vegetable oils, and other solid vegetable fats.
Sugar, generally speaking, is of four kinds, cane, grape, malt, and milk sugar. The sugar from beets, being chemically the same as that from sugar cane, comes under the head of cane sugar. In the making of refined sugar, the canes or the beets are first squeezed between rollers or presses to extract the juices. These juices are then evaporated to the sirup point, and the sirup is crystallized and separated from the molasses. The final result is the modern sugar of commerce.
Cane Sugar is not digested by saliva, but by the intestinal juices after it passes through the stomach; and if delayed too long in passing, it is likely to ferment.
Grape Sugar is found in fruit and honey. It is absorbed with-. out digestion, and is perfectly wholesome.
Malt Sugar is found in sprouting grains. That is, the grain, in sprouting, acts upon the starch within itself, changing it to sugar. This is really an act of digestion. Sprouted grain is mixed with scalded starch at 140° F. (Water at 150° is added to the starch, which cools it to 140°. Anything hotter than this, would destroy the action of the malt on the starch.) This is kept warm, and stirred occasionally; and in a few hours, the starch is changed to sugar. From this process come some of our best sirups.
Milk Sugar is contained in milk, and, like grape sugar and malt sugar, is natural and wholesome.